Use of iodine for improving phase quantification using x-ray tomography
An actual study deals with the ability to quantify synthesised hydration products by incorporating a contrast agent to improve segmentation between the hydration products in portland cement.
X-ray computed tomography (CT) has been used to quantify pore structure and crack characterisation in cementitious materials.
However, similar contrast (greyscale values) of the hydration products in the reconstructed image volume has limited the ability to quantify these phases, and this remains a significant need to further the impact of this experimental method.
The goal of an actual study was to improve the ability to quantify synthesised hydration products by incorporating a contrast agent to improve segmentation between the four main hydration products in portland cement; C-S-H, calcium hydroxide (CH), monosulfate (AFm), and ettringite (AFt).
Using iodine as a contrast agent
Pure C-S-H, CH, and AFt, and a pure and modified AFm, with iodine as a contrast agent, were synthesised for investigation by x-ray CT. Multi-energy scans were used to isolate individual phases using a synchrotron radiation facility. Using iodine as a contrast agent resulted in accurate quantification of the four main hydration products.
The study has been published in Cement and Concrete Research, Volume 116.
